A photo of Mugenroid mode Xenonbine, a 2004 figure from Bandai’s Mugenbine line.
The basic building block of the Mugenbine line was initially the Mugenroid. This chunky 9cm-tall action figure has 14 pegs and 3 peg holes and is capable of folding up into a cube.
One of the neat things about the Mugenroid is each has a unique head sculpt and colour scheme. Each Mugenroid also has an alphabet theme. For instance, Xenonbine, as you might be able to tell from the head sculpt, is the X set.